Ungulates - Midterm Flashcards
Ungulates are comprised of which 2 taxonomic groups?
- Artiodactyla (even toed ungulates)
- Perissodactyla (odd toed ungulates)
What is a RUMINANT?
- Artiodactyla that chews the cud regurgitated from the rumen. Multiple chambers to the stomach!
Key characteristics of the order ARTIODACTYLA?
- Even-toed
- Lack upper incisor teeth
- Small canines or incisoforms
- Cheek teeth are selenodont
- RUMINANT (2 or 4 chambers)
Which 3 families are considered ruminants?
- Cervidae (moose, elk, deer, caribou)
- Bovidae (bison, mountain goat, bighorn sheep, cows
- Antilocapridae (pronghorn sheep, not in BC)
Key characteristics of the order PERSSODACTYLA?
- Odd-toed
- Ulna and fibula are reduced
- Absent collar bone
- Lower canine teeth usually present
- Lophodont teeth
- Simple stomach, monogastric (not chambered)
- Elongated cecum
What is SELENODONT?
- Elongated primary cusps in anterior-posterior direction (cheek teeth of cervidae and bovidae)
What is LOPHODONT?
- Elongated ridges called lophs that run between cusps
What is BRACHYODONT?
- Low crowned teeth (opposite of hypsodont) (humans!)
- Browsers
What is HYPSODONT?
- High crowned teeth that extend far beyond gumline (cows and elk)
- Grazers
What is BUNODONT?
- Cheek teeth with low rounded cusps (broad diet) (humans, bears, pigs)
Define AQUATIC and provide an example
- An animal that SWIMS
- Otter, beaver
Define VOLANT and provide an example
- An animal that GLIDES
- Flying squirrel
Define CURSORIAL and provide an example
- An animal that cursors (RUNS FAST) for long distances
- Carnivores, ungulates
Define SCANSORIAL and provide an example
- An animal is a climber
- Mountain goat, woodpecker
Define ARBOREAL and provide an example
- An animal that spends most of its time in trees
- Squirrels
Define SALTATURTIAL and provide an example
- An animal that is a hopper
- Deer mice, rabbit
Define FOSSORIAL and provide an example
- An animal that digs, usually living in burrows
- Pocket gopher, Badger
What are two factors that determine the speed an animal can travel?
- Length of stride
- Rate of stride (number/time)
Define PLANTIGRADE and provide an example
- An animal that places full length of their foot on the ground
- Humans, bears, raccoons, porcupines
Define DIGITIGRADE and provide an example
- An animal that walks on its digits but not the soles of the feet
- Dogs, Cats
Define UNGULIGRADE and provide an example
- An animal that walks on their tiptoes, often on hooves
- Deer, Horses
Provide 4 adaptations that may lengthen stride.
- Using different parts of the FOOT
- Lengthen the LIMB elements, elongating the digits
- Include the SCAPULA as part of the limb
- Flexing the SPINE
Describe 2 adaptations for increasing frequency of steps.
- Muscle near the joints
- Ulna of cursors is typically reduced or fused
- Fibula and tibia reduced in weight
- Number of digits reduced
What are the 4 main chambers of a ruminant’s stomach?
- RUMEN
- RETICULUM
- OMASUM
- ABOMASUM
What is the purpose of the RUMEN?
- Where fermentation happens
- Provides anaerobic environment containing billions of bacteria which helps breakdown cellulose
- This is where 70% of cellulose is absorbed
What is the purpose of the RETICULUM?
- Where food is compacted into cuds for regurgitation
- Allows for further breakdown by the teeth
What is the purpose of the OMASUM?
- More breakdowns occur
- No digestive enzymes yet
What is the purpose of the ABOMASUM?
- True stomach
- Glands secret hydrochloric acid and pepsin and lipase for final breakdown and absorption
When does rumination occur any why?
- Rumination occurs when the animal is at rest which allows for better digestion and absorption of nutrients
Which family has ANTLERS, what is their structure, and how do they grow?
- CERVIDAE have antlers (only males except caribou)
- BRANCHED
- Grows from pedicle and regulated by testicular and pituitary hormones (stimulates growth in April and May)
- Covered in velvet which carries blood vessels and nerves
- Replaced by compact bone
- Shed in winter
Which family has HORNS, what is their structure, and how do they grow?
- BOVIDAE have horns (both males and females)
- Never branched
- Bony core, with keratin sheath
- Do NOT shed
- Never stop growing
What triggers antler growth, and generally when does this happen?
- The PITUITARY HORMONE
- In SPRING (April/May)
What family do Antelope belong to?
- ANTILOCAPRIDAE
How does the family ANTILOCAPRIDAE differ from other families in the order ARTODACTYLA?
- They have horns, but they are branched and the sheath of keratin is shed annually
Which species are considered GRAZERS?
- Mountain goat
- Elk
- Mule deer (summer)
Which species are considered BROWSERS?
- White-tailed deer
- Moose
- Mule deer (winter)
Which species are considered INTERMEDIATE?
- Caribou
- Mule deer
What is the critical limiting factor for mountain goats?
- Winter habitat
Why is rumination an advantage?
- Makes digestion more efficient, therefore increases nutrient absorption
